SONY MDRRF830
Manual de Servicio

SECTION 2 ELECTRICAL ADJUSTMENTS
Notes: 1. Use transmitter with check and adjustment alreadycompleted. 2. The transmitter section adjustments should be completed before performing the headphones section adjustment. 3. On adjusting the headphones section, use the transmitter as a jig. Headphones MDR-RF830 Transmitter TMR-RF830R

Separation check and adjustment
1. Set the transmitter channel to CH2. 2. Set the transmitter noise filter SW to OFF . 3. Input a signal of 1kHz 316mVrms to onl y the transmitter L4. 5. 6. CH (J403). Connect an digital voltmeter (AC range) and oscilloscope to the L-CH speaker outputs (both sides of MDD01). Receive signals by turning the TUNING VOL (RV302). Adjust the VOL (RV301) so that the RX board L-CH speaker outputs (both sides of MDD01) are 155mVrms. Connect an digital voltmeter (AC range) and oscilloscope to the R-CH speaker outputs (both sides of MDD02) and measure the voltages. At this time, check to make sure the level separation of L-CH and R-CH speaker outputs is more than 20dB. If the separation

Procedure:
AF OSC L-CH (J403) 1kHz 316mVrms (�7.8dB) Jig

7.

ATT

8.
Transmitter 600 � J404 power supply (DC 9V)

1. Feed a signal to jig (transmitter) and connect a power supply to DC IN 9V jack (J404).

Receive frequency check and adjustment
1. Set the transmitter channel to CH2. 2. Set the transmitter noise filter SW to OFF . 3. Input a signal of 1kHz 316mVrms to onl y the transmitter LCH (J403). 4. Place transmitter and headphones at a distance of more than 5m apart. 5. Set the VOL (RV301) to MIN. 6. Position RX board TUNING VOL (RV302) to the center . 7. Connect a digital voltmeter (DC range) and an oscilloscope between IC301 pin @¡ and GND. 8. First check to make sure that a demodulated waveform of 1kHz (appr oximately 13mVrms) is outputted to the oscilloscope , then check to make sure the DC voltmeter reading is DC 1 to 1.2V . 9. If a demodulated waveform of 1kHz is not outputted to the oscilloscope or if the DC level is not within the range specified above, adjust the RX board L301 so that a demodulated waveform of 1kHz is outputted to the oscilloscope and while the wave-form is outputted, further fine adjust the L301 so that the DC voltmeter reading is DC1.1V. 10. When completed, make sure signals can be received when switching the transmitter channel to CH1 or CH3 by turning RX board TUNING VOL (RV302).

is less than 20dB, turn R V303 on the RX boar d so that the RCH output is minimal, then check to see if the level separation of L-CH and R-CH speaker outputs is more than 20dB. 9. Input a signal of 1kHz 316mVrms to only the transmitter R-CH (J402). 10. Adjust the VOL (RV301) so that the RX boar d R-CH speaker outputs (both sides of MDD02) are 155mVrms. 11. Connect an digital voltmeter (AC range) and oscilloscope to the L-CH speaker outputs (both sides of MDD01) and measure the voltages. 12. At this time, check to make sure the level separation of L-CH and R-CH speaker outputs is more than 20dB.

Connection points and Adjustment Location: RX BOARD (See page 5)

Connection points and Adjustment Location: RX BOARD (See page 5)

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